From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 42FB6198E75; Fri, 25 Apr 2025 18:22:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745605330; cv=none; b=Euy93h9zto296+95RmZ3yXtXmiCSroNSGjZqA3m+GSqqD/fFAV/QtRngUzRmDFeblGy+cGbrHlsfZeQOAYK6QztTVyY4J12dROdc7OqhAeCy21S0QXT3mpQmIQw8BsVfwzdw7EUp6mKFN/3HSZppJ1xPh314O7DSc0pSTbgOy1A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745605330; c=relaxed/simple; bh=h/4Eajx1BB93vPcjQ+W2ynlD2GoC8tcFi87iz9uYlDc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=YjAfIMVWXBiqxB1UUfqt5uGNI4XvfU4pDwN+SZCMAq6I2kWREFuD40vkx3rEM7NDrMSp5R5EKpdV84USREGM+4+P0WBNisi0eLcIQmrqmTcajrZcj9X284jkSIq3VyjVBEZj21TK3Axh0Txy96o1NEeOnfW9dhIWShq+o+nDFqU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=NCQ0Mw5F; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="NCQ0Mw5F" Received: from [10.16.80.157] (unknown [131.107.147.157]) by linux.microsoft.com (Postfix) with ESMTPSA id 89D1120BCAD1; Fri, 25 Apr 2025 11:22:08 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 89D1120BCAD1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1745605328; bh=GQxtF7jZT692Xg2kvpz9fFHAy7AjVV3zrXUfHqtyLPc=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=NCQ0Mw5FVpqSQI6GuSPdLS9Cl4TmaROvR7+mdZmykj1KFoZTIgITHgeZJ4zHMt8A4 oF36azBo8C3/PbZaSz/tyqEH0Wu9Dsyk/ebsTARvufmGayBSwsDXgw7OSjfZrbBFgF 4l721r760DtJtIeNBkyirOQQk3qW/xwV6jPAvfKk= Message-ID: Date: Fri, 25 Apr 2025 11:22:08 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [EXTERNAL] Re: [PATCH hyperv-next] x86/hyperv: Fix APIC ID and VP ID confusion in hv_snp_boot_ap() To: Saurabh Singh Sengar , Wei Liu Cc: "bp@alien8.de" , "dave.hansen@linux.intel.com" , Dexuan Cui , Haiyang Zhang , "hpa@zytor.com" , KY Srinivasan , "mikelley@microsoft.com" , "mingo@redhat.com" , "tglx@linutronix.de" , Tianyu Lan , "linux-hyperv@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , Allen Pais , Ben Hillis , Brian Perkins , Sunil Muthuswamy References: <20250424215746.467281-1-romank@linux.microsoft.com> <8fa1045a-c3e9-48e0-86fe-ab554d7475c8@linux.microsoft.com> Content-Language: en-US From: Roman Kisel In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 4/25/2025 10:18 AM, Saurabh Singh Sengar wrote: > >> On 4/25/2025 2:14 AM, Saurabh Singh Sengar wrote: >>>> >>>> On Thu, Apr 24, 2025 at 02:57:46PM -0700, Roman Kisel wrote: >>>>> To start an application processor in SNP-isolated guest, a hypercall >>>>> is used that takes a virtual processor index. The hv_snp_boot_ap() >>>>> function uses that START_VP hypercall but passes as VP ID to it what >>>>> it receives as a wakeup_secondary_cpu_64 callback: the APIC ID. >>>>> >>>>> As those two aren't generally interchangeable, that may lead to hung >>>>> APs if VP IDs and APIC IDs don't match, e.g. APIC IDs might be >>>>> sparse whereas VP IDs never are. >>>>> >>>>> Update the parameter names to avoid confusion as to what the >>>>> parameter is. Use the APIC ID to VP ID conversion to provide correct >>>>> input to the hypercall. >>>>> >>>>> Cc: stable@vger.kernel.org >>>>> Fixes: 44676bb9d566 ("x86/hyperv: Add smp support for SEV-SNP >>>>> guest") >>>>> Signed-off-by: Roman Kisel >>>> >>>> Applied to hyperv-fixes. >>> >>> This patch will break the builds. >>> >>> Roman, >>> Have you tested this patch on the latest linux-next ? >> >> Thanks for your help! Only on hyperv-next, looking how to repro and fix on >> linux-next. The kernel robot was happy, or I am missing some context about >> how the robot works... >> >> What was your kernel configuration, or just anything that enables Hyper-V? >> >> I thought the the linux-next tree would be a subset of hyper-next so should >> work, realizing that have to check, likely there might be changes from other >> trees. >> > > > hyperv-fixes is broken too, here's the log for your ref: > > https://dashboard.kernelci.org/log-viewer?itemId=microsoft%3A20250425085833916790&o=microsoft&type=build&url=https%3A%2F%2Flisalogsb15850d3.blob.core.windows.net%2Flisa-logs%2Fdefault_default%2F20250425%2F20250425-085110-393%2Fkernel_installer%2Fbuild.log%3Fst%3D2025-04-25T09%253A09%253A35Z%26se%3D2025-05-02T09%253A09%253A35Z%26sp%3Dr%26sv%3D2024-11-04%26sr%3Db%26skoid%3D14b53b1d-f4fc-442e-a437-4989376b1754%26sktid%3D72f988bf-86f1-41af-91ab-2d7cd011db47%26skt%3D2025-04-25T09%253A09%253A35Z%26ske%3D2025-05-02T09%253A09%253A35Z%26sks%3Db%26skv%3D2024-11-04%26sig%3DZHfA7%2FC174KR6HT8zhchCb47NE1aceqw8h0APzKxsII%253D > > The hv_snp_boot_ap() function in arch/x86/hyperv/ivm.c currently fails to compile. > It looks like the function's argument was changed from 'cpu' to 'apic_id', but internal > references to cpu were not updated accordingly. > > This might have gone unnoticed during your testing if CONFIG_AMD_MEM_ENCRYPT > was disabled, in which case this function wouldn't have been compiled. Must be the case! I did run the command to merge the CVM specific config options but I didn't check the result. Yep, I see the issue. Will resend the patch. > > Regards, > Saurabh -- Thank you, Roman